[PATCH] TODOs and minor changes

Hello,

attached patch fixes this TODO:

o  MARK_FEED_READ/MARK_FEED_UNREAD in thread level with no selected/ 
tagged
    arts and selecting 'a' marks the base-art read/unead, not the one  
the
    crsr is pointing at.
    [20090815 Urs Janssen <[email protected]>]

This one:

o  GROUP_MARK_THREAD_READ doesn't work on tagged theads, just ranges
    [20090814 Urs Janssen <[email protected]>]

I cannot confirm. It depends on tinrc.mark_ignore_tags. If this is  
OFF, it works on tagged threads, otherwise not. I think this is the  
expected behavior.

Other changes:

- MARK_FEED_UNREAD now sets ART_WILL_RETURN instead of ART_UNREAD  
(like MARK_ARTICLE_UNREAD, MARK_THREAD_UNREAD...).

- Suppress the prompt for GLOBAL_SET_RANGE and GROUP_SELECT_PATTERN  
(group.c:group_page()) when no articles available.

- Two fflush(stdin) calls removed (actually I made it a comment).  
fflush() is not defined for (pure) input streams. The comment above  
the first call refers to a reconnection issue which I couldn't  
trigger the last two weeks. If this reconnection issue (or any other  
issue related to this) comes up again we should fix this not relying  
upon undefined behavior.

Dennis